Journal of Oceanography, Vol. 61 (No. 1), pp. 155-165, 2005
Sunghyea Park1*, Moon-Sik Suk1 and Hui Soo An2
1Marine Environment and Climate Change Laboratory, Korea Ocean Research & Development Institute, Ansan 426-744, Korea
2Department of Earth Science Education, Seoul National University, Seoul 151-742, Korea
(Received 24 February 2004; in revised form 28 May 2004; accepted 29 May 2004)
Abstract: Numerical experiments were performed in order to investigate the effects of variations of the transport through the Korea/Tsushima Strait, an inlet of the Japan/East Sea, on the upper layer circulation in the JES based on a 10-month transport observation from May 1999 to March 2000 (Perkins et al., 2000). All external forcings to the model were annual mean fields, except the transport variation through the Korea Strait. In the experiments where the periodic variation of the transport repeated continuously sinusoidally by several periods, strong variability of sea surface height (SSH) was detected in the region extending from the Korea Strait to the Japanese coast due to the geostrophy of the buoyancy forcing at the Korea Strait. The region along the Korean coast is more sensitive to the long-term variations than the short-term (60-day period) ones. In two experiments forced by realistic and monthly mean transport, the difference of rms of sea surface height was largest at the Japanese coast and relatively large at the East Korean Warm Current separation region (128~130°E, 39~41°N) and to the east of Yamato Rise. The distribution of difference of eddy kinetic energy at 100 m depth between the two experiments was similar to that of the rms of SSH. In the distributions of mean SSH and mean kinetic energy at 100 m depth the realistic transport invokes eddy variability to interact with mean current resulting in the changes of the mean SSH and the mean kinetic energy at the East Korean Warm Current separation region, but it does not produce conspicuous changes in the mean fields of entire JES compared with the mean fields forced by the seasonal transport.